Joy and Jonathan's marriage wasn't exactly on the rocks, but it was getting a little shaky, as Jonathan appeared to be drifting away. When Joy found some hidden papers in her husband's study, she was shocked at what she learned. Jonathan had a ready explanation that sounded credible, and Joy appeared to accept it, but did she really believe him? And would he risk losing her and her trust fund millions?
What happened then was totally unexpected, and though perhaps a bit unlikely, it made for a good story with an O'Henry-style ending.
NOTE: After I got a few pages into the story, I thought that the cover art was foreshadowing the outcome. The knife that Joy is holding does factor into the story, but in a most unexpected way.